Apparatus fob charging boners



NOV. 20, 1934. G WHEAT 1,981,210

APPARATUS FOR CHARGING MINERS LAMPS Filed Dec. 28, 1932 2 Sheet-Sheet 1giATToRA/Ey,

Nov. 20, 1934. W EAT 1,981,210

APPARATUS FOR CHARGING MINERS LAMPS Filed Dec. 28, 1932 2 Sheets-Sheet 2AT'I'OR/VEV I Patented Nov. 20, 1934 UNITED STATES PATENT OFFICE GrantWheat, Marlbo Koehler Manufacturing Masa, a corporation of ro, Masa,assignor to Company, Marlboro, Massachusetts Application December 28,1932, Serial No. 649,145

This invention relates to miners lamps and is more especially concernedwith the charging apparatus for such lamps.

A miner's lamp comprises a headpiece carrying one or more electric lampsand equipped with means for fastening the headpiece on a miner's cap. Italso includes a storage battery which usually is slung from the minersbelt, and a cord provided with suitable conductors for supplying currentfrom said battery to the electric lamp in the headpiece. It is necessaryto recharge the battery at intervals-and it is the usual practice forthe miner to turn in his lamp at the lamp house upon leaving the mine sothat the battery can be charged during his absence and will be in properworking order when he again goes into the mine. In order to reduce theduties of the lamp house attendant it is a common practice in some minesto require the miner to place his lamp properly in the charging rack andto do the simple acts necessary to put the battery on charge. Either dueto carelessness or ignorance, or both, some miner frequently neglects toperform these operations properly, with the result that he goes into themine'with a poorly charged battery.

The present invention deals especially with these conditions. It aims todevise a charging apparatus of such a nature that it will be practicallyimpossible for a miner to place his lamp improperly in it. In otherwords, it is the chief object of the invention so to improve lampcharging apparatus that the proper mounting of the lamps in chargingposition will be facilitated, and the failures to so place the lampswill be minimized.

The nature of the invention will be readily understood from thefollowing description when read in connection with the accompanyingdrawings, and the novel features will be particularly pointed out in theappended claims.

In the drawings, 7

Figure 1 is a perspective view of a portion of a charging rackconstructed in accordance with this invention and illustrates a miner'slamp in charging position;

Fig. 2 is a front elevation of parts of the rack shown in Fig. 1;

Fig. 3 is a bottom view of certain 01' said parts;

Fig. 4 is a front view of the more important elements at one station ofthe rack shown in Fig. 1, and illustrates a lamp headpiece in,chargingposition;

Fig. 5 is a side view of a portion of the lamp headpiece;

Fig. 6 is a side view on a larger scale of the guide for receiving theoperating element of the switch;

Fig. 7 is a perspective view of a headpiece with some of the partsbroken away; and

Fig. 8' is a diagrammatic view of the wiring in the headpiece.

Referring first to Fig. 7 the headpiece 2 there shown is substantiallylike that shown and described in my copending application Serial No.615,115, filed June 3, 1932, andincludes an insulating casing carrying aspring clip 3 for securing it to the lamp attaching plate on the miner'scap. Mounted in the headpiece is a main electric lamp 4 equipped withtwo filaments 5 and 6, this lamp being located centrally in front of areflector 7. A small electric lamp 8, intended simply' for emergencyuse, also is supported in the headpiece. The two conductors which carrycurrent from the storage battery 9, Fig. 1, to the headpiece extendthrough and form part of the insulated cord or cable 10, and one ofthese conductors leads to the central terminal of the lamp 4 while abranch leads to one terminal of the emergency lamp 8. The otherconductor is connected directly to the rotating member 12 of a rotaryswitch which is mounted in the side of the headpiece, this switch beingprovided outside the headpiece with an operating element which consistsof a rotary insulating button or handle 13. The outer terminals of thelamp filaments 5 and 6 lead, respectively,

to switch terminals 14 and 15, Figs. 7 and 8, while the other terminalof the emergency lamp 8 is connected to a switch terminal 16.Consequently, by rotating the button or handle 13 either of thefilaments 5 or 6 of the main lamp, or the filament of the emergencylamp, may be lighted, as desired.

One of the supply conductors leading from the battery is connectedthrough a thermostatic switch 17, Fig. 8, to a charging terminal 18which is mounted in an exposed position at one side of the neck or shankof the headpiece, as best shown in Figs. 4 and '7, while the otherconductor is connected to a second charging terminal 19, Fig. 4, locatedat the opposite side of said shank. Additional conductors connect thelatter terminal with a switch terminal 20 located in cooperativerelationship to the rotary switch member 12. When the terminals 18 and19 on the opposite sides of the shank of the headpiece are connected toa pair of charging terminals leading from a generator or other source ofcurrent supply, the char ing current is for a time prevented fromflowing through the battery for the reason that static switch 1'7. Theheating coil of this switch is connected directly across the terminals18 and 19, as shown in Fig. 8, and consequently, the current flowsthrough this coil, thus heating the bi-metallic switch element andcausing the latter to warp or bend until it finally closes this switch.If, at or prior to this time, the switch 12 is moved on to the contact20, the current then will flow through the battery and will charge it,but current will also continue to flow through the coil of thethermostatic switch and will hold this switch closed so long as chargingcurrent is supplied to the terminals 18 and 19. These circuits and theiruses are explained more fully in the specification of my "pendingapplication above referred to.

When the miner places his lamp in the charging rack to be charged, he issupposed to turn the switch 12 into contact with the charging terminal20, thus extinguishing either lamp 4 or 8 which has been lighted, andplacing the circuits in condition for charging. This he fails at timesto do, with the result that his battery is not properly charged. Thepresent invention provides an arrangement for preventing thisdifliculty.

Referring more especially to Figs. 1- to 6, ,inclusive, it will beobserved that the charging rack includes an upright panel 22 providedwith a series of stalls or stations each adapted to receive a headpiece2. At each station two spring charging terminals 23 and 24 are providedto engage, respectively, with the charging terminals 19 and 18 on theshank of a headpiece. These spring terminals are of opposite polarities,all of the terminals 23 being connected to a bus bar 25 which extendshorizontally along the panel, while all of the terminals 24 areconnected to another bus bar 26 located below and parallel to the bar25. The two bars are connected to opposite terminals of a chargingcircuit. 'Just above each pair of charging terminals and set backwardlyaway from them is a notched block 27 of insulating material providedwith corners which are bevelled, as indicated at 28. The enlargedportion of the headpiece sets into this notch in the block 27 when theshank of the headpiece is forced between the charging terminals 23 and24 into such a position that these terminals are engaged by the contacts19 and 18, the weight of the headpiece being supported by the block. Theheadpiece should be pushed back until it brings up against a spacingstrip 30, Fig. 1. The headpiece then is in proper position for thecharging operation to proceed.

At one side of each station or stall in the rack a second block 31is'secured, this block projecting forward beyond the block 27 andoverlying one end of the latter block. Formed in the block 31 is atapered groove or guideway 32 which is so shaped and positioned as toreceive the flangelike extension 33 which projects from the outer faceof the switch handle or button 13. An arrow 34, Fig. 5, on the side ofthe headpiece cooperates with the flange 33 to designate the chargingposition of the switch button. In other words, when the flange 33 pointsto the arrow 34, as shown in Fig. 5, the rotary switch blade 12 thenwill be in contact with the charging switch terminal 20, Figs. '7 and 8.When the button is in this position the headpiece can be pushed freelyinto any one of the recesses or stalls provided to receive it in therack, and the charging terminals 18 and 19 on the shank of the headpiecewill then be in proper engagementwith the charging termipiece may beproperly placed in the rack notwithnals 24 and 23 on the'rack. 0n theother hand, if it is attempted to place the headpiece in chargingposition when the switch operating button 13 is out of charging positionby any substantial amount, the flange 33 then will engage the front faceof the block 31 and it'will be impossible to force the headpiece backfar enough to push the shank between the charging terminals 23 and 24.If, however, the button is only slightly out of charging position, thenthe thin end of the extension 33 will enter the slot or guideway 32 and,as the backward movement of the headpiece is continued, the engagementof said flange with the walls of the guideway will rotate the switchbutton 13 into its charging position and the headstanding the faultyinitial position of the switch. In other words, this error in positionwill be corrected automatically. It should also be noted that if it wereattempted to place the headpiece in position by making it override theblock 31, such an attempt would be prevented by the presence of theprojecting strip 35, Fig. 1, which extends horizontally from the panel22 into such a position that this strip closely overlies the upper edgesof the headpieces when they are properly v located in charging position.The invention thus provides a charging rack which facilitates the propermounting of the lamps correctly for the charging of the batteries. It isso constructed that it positively prevents the placing of a headpiece incharging position unless the switch is substantially in the correctposition to permit the charging operation to proceed. On the other hand,if the switch is only slightly out of the proper position, then themovement of the headpiece into the rack automatically moves the switchinto correct charging position. This construction thus materiallyassists the miner in properly placing his lump on charge and deflnitelyprevents a misplacement of it.

While I have herein shown and described a preferredembodiment of myinvention, it will be understood that the invention may be embodied inother forms without departing from the spirit or scope thereof.

Having thus described my invention, what I desire to claim as new is:

1. In a charging rack for miners lamps of the type in which theheadpiece is provided with a. switch in the charging circuit, saidswitch includ- 125 ing an operating element, the combination with meansfor supporting said headpiece in charging position, and meansfor'preventing the movement of said headpiece into said position unlesssaid switch is in substantially its charging position.

2. In a charging rack for miners lamps of the type in whichthe-headpiece is provided with'a switch in the charging circuit, saidswitch including an operating element, the combination with means forsupporting said headpiece in charging position, and means cooperatingwith said supporting means for engaging said operating element as saidheadpiece is moved into its charging position and moving it when it ismisplaced to bring the switch into condition to enable the chargingoperation to proceed.

'3. In a charging rack for miners lamps of the type in which theheadpiece is provided with a switch in the charging circuit, said switchincluding an operating element, the combination with means forsupporting said headpiece in charging position, and means for engagingsaid operating element and moving it to correct a faulty position of theswitch when the headpiece is moved into its charging position.

4. In a charging rack for miners lamps of the type in which theheadpiece is providedwith a switch in the charging circuit, said switchincluding an operating element, the combination with means forsupporting said headpiece in charging position, a guide for saidoperating element arranged to receive said element when it isapproximately in its charging position but operative to cause themovement of the headpiece into charging position to turn said elementinto the correct position when incorrectly positioned.

5. In a charging rack for miners lamps of the type in which theheadpiece is provided with a switch including an operating element andin which also the headpiece is equipped with charging terminals, saidswitch being operable to close the charging circuit, the combinationwith means for supporting a headpiece in charging position, chargingterminals on said rack arranged to be engaged by the charging terminalson said headpiece, and means for preventing the engagement of the twosets of charging terminals with each other unless both said headpieceand said switch are properly positioned for the charging operation.

6. In a charging rack for miners lamps of the type in which theheadpiece is provided with a switch including an operating element andin which also the headpiece is equipped with charging terminals, saidswitch being operable to close the charging circuit, the combinationwith means for supporting a headpiece in charging position,

charging terminals on said rack, said rack having arecess to receive theheadpiece when said charging terminals on the headpiece are in properengagementwith the charging terminals on said rack, and means associatedwith said recess for receiving said headpiece and said operating elementoi said switch when said element is in proper position for the chargingoperation, said means being arranged to prevent the movement of saidheadpiece into charging position unless said switch is approximately inits charging position.

'1. In a charging rack for miners lamps of the type in which theheadpiece is provided with a switch including an operating element andin which also the headpiece is equipped with charging terminals, saidswitch being operable to close the charging circuit, the combinationwith means for supporting aheadpiece in charging position,

charging terminals on said rack-arranged to be engaged by the chargingterminals on said headpiece, said rack having a recess to receive theenlarged portion of said headpiece when said charging terminals on theheadpiece are in proper engagement with the charging terminals on saidrack, the charging terminals on said rack being so located withreference to said recess as to compel' the placing of the headpiece in apredetermined relationship to the rack, and a guide at one side of saidrecess for receiving said switch operating element, said guide beingconstructed to hold the switch in a predetermined relationship to saidheadpiece.

GRANT WHEAT.

enlarged portion of said

